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Related papers: Orientable sequences over non-binary alphabets

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This paper describes new, simple, recursive methods of construction for orientable sequences, i.e. periodic binary sequences in which any n-tuple occurs at most once in a period in either direction. As has been previously described, such…

Combinatorics · Mathematics 2026-03-20 Chris J Mitchell , Peter R Wild

Analogously to de Bruijn sequences, Orientable sequences have application in automatic position-location applications and, until recently, studies of these sequences focused on the binary case. In recent work by Alhakim et al., recursive…

Combinatorics · Mathematics 2026-03-20 Chris J Mitchell , Peter R Wild

Analogously to de Bruijn sequences, orientable sequences have application in automatic position-location applications and, until recently, studies of these sequences focused on the binary case. In recent work by Alhakim et al., a range of…

Combinatorics · Mathematics 2026-03-20 Chris J Mitchell , Peter R Wild

Orientable sequences of order n are infinite periodic sequences with symbols drawn from a finite alphabet of size k with the property that any particular subsequence of length n occurs at most once in a period in either direction. They were…

Combinatorics · Mathematics 2026-03-20 Chris J Mitchell , Peter R Wild

Orientable sequences, periodic sequences in which any $n$-tuple appears at most once in either direction, were introduced in the early 1990s for use in certain position location applications; constructions and upper bounds on the period for…

Combinatorics · Mathematics 2026-03-20 Chris J Mitchell , Peter R Wild

An orientable sequence of order $n$ is a cyclic binary sequence such that each length-$n$ substring appears at most once \emph{in either direction}. Maximal length orientable sequences are known only for $n\leq 7$, and a trivial upper bound…

Data Structures and Algorithms · Computer Science 2024-05-27 Daniel Gabric , Joe Sawada

Negative orientable sequences, i.e. periodic sequences with elements from a finite alphabet of size at least three in which an n-tuple or the negative of its reverse appears at most once in a period of the sequence, were introduced by…

Combinatorics · Mathematics 2026-02-09 Chris J Mitchell , Peter R Wild

In some particular cases we give criteria for morphic sequences to be almost periodic (=uniformly recurrent). Namely, we deal with fixed points of non-erasing morphisms and with automatic sequences. In both cases a polynomial-time algorithm…

Discrete Mathematics · Computer Science 2007-05-23 Yuri Pritykin

An orientable sequence of order $n$ over an alphabet $\{0,1,\ldots, k{-}1\}$ is a cyclic sequence such that each length-$n$ substring appears at most once \emph{in either direction}. When $k= 2$, efficient algorithms are known to construct…

Discrete Mathematics · Computer Science 2024-07-10 Daniel Gabrić , Joe Sawada

We consider the complexities of substitutive sequences over a binary alphabet. By studying various types of special words, we show that, knowing some initial values, its complexity can be completely formulated via a recurrence formula…

Combinatorics · Mathematics 2015-07-16 Bo Tan , Zhi-Xiong Wen , Yiping Zhang

Let $\widetilde{\alpha}$ be a length-$L$ cyclic sequence of characters from a size-$K$ alphabet $\mathcal{A}$ such that the number of occurrences of any length-$m$ string on $\mathcal{A}$ as a substring of $\widetilde{\alpha}$ is $\lfloor L…

Combinatorics · Mathematics 2022-06-24 Abhinav Nellore , Rachel Ward

This paper presents a method to find new De Bruijn cycles based on ones of lesser order. This is done by mapping a De Bruijn cycle to several vertex disjoint cycles in a De Bruijn digraph of higher order and connecting these cycles into one…

Combinatorics · Mathematics 2008-12-23 Abbas Alhakim , Mufutau Akinwande

After giving an overview of the existing theory regarding the periods of sequences defined by linear recurrences over finite fields, we give explicit descriptions of the sets of periods that arise if one considers all sequences over…

Number Theory · Mathematics 2021-07-28 Michael R. Bush , Danjoseph Quijada

In this paper, the construction of finite-length binary sequences whose nonlinear complexity is not less than half of the length is investigated. By characterizing the structure of the sequences, an algorithm is proposed to generate all…

Information Theory · Computer Science 2023-12-27 Sicheng Liang , Xiangyong Zeng , Zibi Xiao , Zhimin Sun

Nonlinear complexity, as an important measure for assessing the randomness of sequences, is defined as the length of the shortest feedback shift registers that can generate a given sequence. In this paper, the structure of n-periodic binary…

Information Theory · Computer Science 2026-02-03 Qin Yuan , Chunlei Li , Xiangyong Zeng

Let us call a sequence of numbers heapable if they can be sequentially inserted to form a binary tree with the heap property, where each insertion subsequent to the first occurs at a leaf of the tree, i.e. below a previously placed number.…

Data Structures and Algorithms · Computer Science 2010-07-15 John Byers , Brent Heeringa , Michael Mitzenmacher , Georgios Zervas

Nonlinear complexity is an important measure for assessing the randomness of sequences. In this paper we investigate how circular shifts affect the nonlinear complexities of finite-length binary sequences and then reveal a more explicit…

Information Theory · Computer Science 2024-04-26 Qin Yuan , Chunlei Li , Xiangyong Zeng , Tor Helleseth , Debiao He

We introduce the classes of descendingly flexible and descendingly alternative algebras over an arbitrary field $\mathbb{F}$. We suggest a new method based on the sequence of differences between the dimensions of the linear spans of words,…

Rings and Algebras · Mathematics 2023-12-07 Alexander Guterman , Svetlana Zhilina

We define an algorithm that parses multidimensional arrays sequentially into mainly unrepeated but nested multidimensional sub-arrays of increasing size, and show that the resulting sub-block pointer encoder compresses almost every…

Information Theory · Computer Science 2014-08-20 Tyll Krueger , Guido Montufar , Ruedi Seiler , Rainer Siegmund-Schultze

We prove that the uniform recurrence of morphic sequences is decidable. For this we show that the number of derived sequences of uniformly recurrent morphic sequences is bounded. As a corollary we obtain that uniformly recurrent morphic…

Combinatorics · Mathematics 2012-09-03 Fabien Durand
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